Medicare beneficiaries who miss the midnight deadline Monday will not be able to choose a prescription drug plan until November, and they will have to pay an extra 1 percent per month for their premium.

Cunningham said it "scares" her that people will wait until the last moment and might not be able to get through busy lines for help in signing up for a plan.

"Now we're getting lots and lots of calls. They're really waiting until the last minute. We didn't want them to do that."

Children can give their mother a Mother's Day gift by checking on their drug benefits and helping them sign up for a plan if needed, she said.

Officials had estimated that about 30,000 of Hawaii's 186,000 Medicare beneficiaries needed to choose a Part D drug plan. Others have state, federal or union retirement benefits or are still working and have private medical coverage.

About 151,691 isle Medicare beneficiaries were enrolled in prescription drug plans as of Sunday, according to the Centers for Medicare and Medicaid.

The figure includes 9,568 with a stand-alone prescription drug plan; 50,267 in Medicare Advantage plans with prescription drugs; and 24,014 Medicare-Medicaid recipients who were automatically enrolled in a drug plan.

Cunningham said Sage PLUS volunteers will take calls through the weekend.

The Elderly Affairs Division on Oahu also will provide whatever assistance it can if people call its senior hot line, 523-4545, said Karen Miyake, county executive on aging.

"At least call," she said, pointing out the Medicare Part D program "might provide significant benefit for many seniors."

People calling for help should have their Medicare card and a list of prescriptions.

Medicare's toll-free hot line, 800-MEDICARE (633-4227), is open 24 hours a day and will be available to Hawaii residents up to midnight Monday, Cunningham said.

"So if a person tries to call them to apply for extra help at 10 p.m., our time, they'll respect that."

Applications also will be accepted as long as they are postmarked by midnight May 15, she said. "It's kind of like taxes, except they won't have people grabbing the mail."

People also can go online for help at www.medicare.gov.

Cunningham suggested that people call the toll-free Medicare number if they are waiting until the last minute to choose a drug plan. They might have to be on hold awhile, but they should not give up, she said.

Sage PLUS volunteers will be working until about 9 p.m. over the weekend, but they might not get back to people leaving a message for an hour or so, she said.

A lot of people calling have HMSA 65-C Plus cards and do not realize they already have Part D coverage, Cunningham said. The card should say "Medicare RX" in the bottom right corner.

Those who have old HMSA cards that say "drug discount" should throw them away, she said.

Cunningham said 100 percent participation is not expected since the Part D drug program is not mandatory.

But people with high drug costs who have not enrolled "really need to," she said. "It would help them."